@beelee Yes, I confirm. It is so, and it is so since some months I join the lobby. It was not so in the past, so I'm guessing it is a bug or, anyways, I can't think it may be a behaviour anybody intended.
I'm sure some recall that in the past the right column was reasonably sized, not ridiculously wide like now, joining the lobby.
I think it started when the lobby was made anew, like half a year ago.
But this is my experience, so I don't really know, since you say "I've been doing for years". Are you sure you recall correctly?

My suggestion is that the part showing the hosted games (upper-left) is set default at 80% of the total.
It feels really unpolished / unprofessional joining the lobby and visualising a display clearly with no setting, or apparently so.
I'm just not sure if this is a feature request or a regression, as I can only speak for myself, joining the lobby.
What was anyone else's experience like 1 year ago or more?